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Picked some up off here 2nd hand, however not sure I have the original bolts with them, as when mounted with the tri-alignment washers etc., there's not much bolt peeking through to mate into the post mount on the forks.
Wouldn't be so bothered if it was onto an adaptor but going straight into the fork, don't want to risk stripping the thread.
How long are your BB7 mounting bolts, if anyone could check?
You should have 4mm or so of thread showing.
4mm - thats not much - I'd measure it all up including the depth of the holes and buy bolt to suit
Rule of thumb for thread engagement is no less than 1.5x the diameter.
M6 bolt needs at least 9mm of thread engaged.
just measured a bolt off a set i have ( also bought SH and not yet fitted ). M6 x 30.
Have some sat on bench that I've had from new bolts as above M6x30
I has this problem with BB7 road versions recently. To stop the caliper fouling the rotor hardly any thread was engaged. I couldn't figure out what I was doing wrong.
I got a set of these: https://www.merlincycles.com/avid-post-spacer-set-20s-69933.html?utm_campaign=googlebase-GB&utm_source=googlebase&utm_medium=shopping&utm_term=MTB+Disc+Brake+Rotors+%26+Spares&gclid=CjwKEAiAoaXFBRCNhautiPvnqzoSJABzHd6h_cTpn2gTLNUK_XHv0I0LOQ_4hfaLKpY2BEcBAOhUexoC2uDw_wcB and it seems to have helped. They are much longer and have better looking spacers too.
I replaced mine with stainless bolts, but just make sure you get 1.5x to 2x the nominal diameter in thread engagement and you'll be sweet.
You sometime have to be towards the lower end of that range on post mount holes because there's not enough depth to the thread (IME).